The location where the diagnostic action will be triggered,
relative to a joinpoint. A joinpoint is a specific location in
a class, for example a method or a call site within a method.
Locations can be:

Before specifies that the diagnostic activity will occur
before the joinpoint.

After specifies that the diagnostic activity will occur
after the joinpoint.

Around specifies that the diagnostic activity will occur
both before and after the joinpoint.

An ellipsis (...) in the argument list signifies a variable
number of arguments of any types beyond the argument.

A % (percent character) prefix designates the value
of a non-static class instantiation, parameter, or return
specification as not containing nor exposing sensitive information.
If this prefix character is not explicitly used, an asterisk string
is substituted for the value that is returned. Note that the
% operator cannot be applied to an ellipsis or to a
wildcarded type within a pointcut expression.